Charge forming device



Oct. 20, 1953 B. c. PHILLIPS 2,656,167

CHARGE FoRMING DEVICE Filed Feb. e, 195o BEHNAHD D. FHLLLJPS. -E

Bg A.

Y ttorneg f Oct. 2.0, 1953 B. c. PHILLIPS CHARGE FORMING DEVICE FiledFeb. e, 195o l Win? 2 Sheets-Sheet 2 BERNARD ZHILLIPS.

.5A/Mig.

nventor:

patented ct. 2:0,

v UNITED STATES PATENT FFCE CHARGE FORMING DEVICE BernadC. Phillips,Toledo, hio, assigor to The Tillotson Manufacturingr Company, Toledo,Ohio, a corporation of Ohio Application February 6, 1950, Serial No.142,630

(Cl. E61-415 A 8 Claims.

This invention relates to charge forming devices for use with internalcombustion engines and more especially to a carburetor wherein the majoroperating components are mounted upon a carburetor body and relates toimprovements upon the charge forming deviee disclosed in the applicationof Edward H, Foster Serial o. 104,225.

An object of the present invention is the provision of a carburetorwherein the fuel reservoir or chamber is made of sheet materialkahd inwhich the valve mechanism controllingnthewfuel flow to the reservoir andthe float mechanism for actuating the Valve are mounted upon thecarburetor body independently off the fuel reservoir construction. Y p yAnother object of the invention resides in the provision of a carburetorconstruction `wherein the operative components ofthe carburetor arecompactly arranged so as to minimize the space occupied by the.carburetor as well as to reduce the cost of manufact'uring the same. 1 i

Anothe1 objectl of' the invention is the provi- 'sion of a carburetor'wherein the' noat controlled valve' mechanism fory regulating the flowof fuel into thev float bowl or fuel` reservoir is completelyindependent of the fio-at bowlv construction whereby the latterA may' beremoved or assembled without disru'pting the float controlled valve andassociated elements. N

Another object.- of the invention is theprovision of4- acarburetorhaving :a float bowlk formed ofi conriparatively` thin sheetmaterial such as brass, copper, aluminum or the like, which issecured`to a` carburetor bodyby'siniple means? which maybe readily manipulatedto assembleV or remove the oat bowl with a. minimum of effort and time.

Another object of the invention is the provision of a fuel meteringmeans especially adaptable for incorporation in charge formingdevicesbei'ng of a character' in which the ow rate of v fuel through themetering inea/lisis SllbStaIltlally unaffected throughout normaloperative temperature ranges of fuel or by changes' viscosity of fuelwithin th'e'range'of usable' fuels. y

A further phase of4 the invention relates to" the provisioni of aIsimple yet effectiveI fuel metering means of' the' fixedl orifice type;the member formed with the ni'eteringk orifice being mounted" in-amanner tofacilitat'e theready interchan'geof members provided withorifices of different s'i'zes" forf securing varyingl riite'sY ot fuelflow'.

Furtheriob'j ects= and`l advantages are within theA scope of thisinvention such as relate to the'l are rangement, operation andi functionof' the' relatedelements of the structure, to various details Vfofconstruction and v,to combinations of parts, elea ments per se, and toeconomies of manufacture and numerous other features as will ,beapparent from a consideration` of the specification and drawing of aform of the invention, which may be preferred,- in which: l Fgure l isra top plan view of a charge forming device or carburetor embodying the,invention;

Figure 211s a vertical longitudinalsectional view taken substantially onthe line 2-2 of Figi ure l; c

Figure 3 is a vertical transverse sectional View taken substantially onthe line Eef-3 of Figure l; Figure 4 is an enlarged detalview showing afuel metering means forming apart of the nven tion; c

"Figure 5 is a sectional view similar to Figure 2 illustrating amodified form of construction.. and Figure 6 is a view similar to Figure5 showing a further form of construction. a Referring to the drawings indetail and first with respect to the form of the invention illus--trated in Figures l through 4Kinclusive, the carburetor includes abodymember I formed with a mixing passage ll having a venturi l2 incommunicationwith anv air inlet passage I4 conv nectedv by a tube l5 ofan air cleaner (not shown). rIhe mixing passage ll is of smallerdiameter than the air inlet i4, the axes of passage Il and` inlet 1 4being eccentrically arranged, the axis; ofthe mixing passage beingnearer the fuel level the receptacle It.V By this arrangement the fueldischarged into the venturi as hereinafter described is lifted but asmall distance above the fuel level in the receptacle to the pointofdischarge. f y Y h Asuitable fuel chamber or fuel reservoir ,ll islprovided for the carburetor and includes a bowl-y iilre member orreceptacle IB formed ot sheet materialas for lexamplegbrass, copperoryany composition yor alloy which is not subject to the corrosiveeffects of the fuel. As, will be seen inFiggV ure 2w the carburetor bodyl0 is formed with anannularly shaped groove 20 adapted toaccom modatetherim or edge of the receptacle i8, a' suitable sealing gasket 2 ibeing' disposed between the rim of` the receptacle andthe walls' ofy thechannel 2s; iii` order to" eirect id tig tser between these elements;vlhiletheI receptacle Il? is illustrated as substantially s'eirisplferal configuration; asthisfshapfaciiitates uis formar tion' ofthereceptaciefromsiieet meter itistte understood that receptacleoffdiffreiit cdiig'ii;

muonJ may be utilized without departing friirthe spirit of theinvention. The carburetor body I is formed with a depending portion 23which has a hollow interior forming a fuel well 2li. The lower portionof the interior well thereof is threaded to receive a plug 26 whichserves to close the lower end of the depending portion 23. The plug 26is formed with a polygonally shaped head 2 which serves to secure thereceptacle I8 in assembled relation with the body iii, an annularsealing gasket 28 being disposed between the head 2l and the receptaclei3 to provide a fluid tight seal. The bolt or plug 26 forms the solemeans for securing the receptacle I8 in assembled relation with thecarburetor body. The carburetor body ii) is formed with a fuel inletpassage SI which includes a horizontal duct 32 and a vertical passage33. The Wall oi the duct 32 is threaded as at 3d to accommodate `acoupling with a fuel supply tube 3 in communication with a fuel supply.The vertical passage S3 of the fuel inlet is threaded as at 35 toreceive and accommodate a fitting 36 the latter having an interior bore3l terminating in a valve seat portion 3S. A valve 39 of non-circularcrosssection is slidably disposed in the bore i in fitting 36 and has acone shaped or needle portion All cooperating with valve seat 3S inorder to regulate or control the ingress of fuel into the float chamberI7.

The body portion I is formed with depending ears c2 which are bored toreceive a pivot pin adapted to support a bracket 44, one arm of' whichis secured as by soldering or other suitable means to a float i5disposed in the float chamber or fuel reservoir I'I. The float member dis preferably fabricated of two annularly shaped cup-like elements iland lil which are joined together as by soldering, brazing or the likeat their overlapping central portions to form an hermetically sealedconstruction. The bracket im is provided with an upwardly extendingportion S which is adapted to engage the extremity of the valve member39 as particularly shown in lfigure 3. The float member :i5 is thusarticulately or pivotally connected to the ear por.. tions 42 of thebody member Iii and, through the medium of the bracket i4 engaging thevalve member 39, controls or regulates the flow of fuel into the floatchamber i1 through the inlet 3|'. As the float member 45 is elevated byreason of the fuel rising in the receptacle Il", pressure is exerted inan upward direction through the bracket 119 to move or bias the valve 39toward closed position, that is, with the needle or tapered portion dengaging the valve seat 3S to interrupt the fiow of fuel into the iioatchamber when the fuel therein reaches a predetermined level.

The mixing passage II is provided with a throttle valve in the forni ofa disc 52 which is mounted upon a transversely extending shaft 53journaled in suitable boss portions ed formed on the carburetor body i.Manipulating means is provide for the throttle valve in the form of anarm 5&5 xedly secured to one extremity of the shaft 5S, a coil spring 5lsurrounding a portion of the shaft 53 and being hooked over the arm 56as shown at 58 in order to resiliently bias the valve 52 toward closedposition. The arm 56 may be connected to a suitable operating rod 60 asshown in Figures 1 and 2.

A suitable valve in the form of a disc-like member 52 is mounted upon atransversely extending shaft 63 which is journaled in suitable bossportions B4 formed integrally with the body portion of the carburetor.One end of the shaft 63 may be bent laterally as at 65 to facilitate themanipulation of the valve 62 in order to control the admission of air tothe carburetor through the air inlet passage I4. Frictional resist-anceis provided for the shaft 63 in order that the air valve may be retainedin an adjusted position. This means is inclusive of a coil spring 6lwhich surrounds a portion of the shaft 63 and abuts against a disc orWasher 68 held in place on the shaft by means of a pin 69. The passageII of the carburetor is in communication with an engine manifold themanifold being secured to a fiange portion 'il of the carburetor body bymeans of suitable bolts l2.

The upper extremity of the depending portion 23 forming the fuel well 24is threaded as at 'I to receive a fitting 75 which is formed with aninterior bore i6 the upper outlet of which forms a main fuel dischargeorifice "i8 into the mixing passage i I. The fuel discharge orificepreferably opens in the zone of the choke band Il of the venturi I2, thechoke band being the point or zone of greatest restriction to the flowof air through the carburetor. The maximum speed of air passing throughthe carburetor exists at the choke band i'i and the high air speedthrough the choke band facilitates the discharge of fuel from the oriceI8 into the mixing passage.

In some installations it is desirable to bleed air into the fuel at thetime 0f its discharge through the main fuel orice. To this end thecarburetor is provided with an air bleed passage or channel whichestablishes communication between the main air inlet Ill and the fuelwell 24. rl`he admission of air to the fuel well through the passage Sprovides for the admixing with the iquid fuel in the fuel well of arelatively small amount of air so that the fuel discharged through themain jet or orifice 'I8 and the main fuel orice is in the form of anemulsion or admixture, that is, having small bubbles of air in the fuel.

r.'he carburetor is provided With means for introducing fuel to themixing passage for idling or slow speed engine operation when thethrottle valve 52 is in closed or substantially closed position.Extending vertically of the carburetor in the embodiment illustrated asshown in Figure 2 is a relatively small tube S2 which depends below thefuel level in the receptacle l'I and extends upwardly terminating in abore 84 in the carburetor body. The upper end of tube 32 extends intothe hollow interior of a fitting 85 which is formed with openings 86 tofacilitate fuel flow into the bore Sd. The bore 84 is in communicationwith a chamber 81 by means of a duct or passage 88. The chamber 81 is incommunication with the mixing passage I I by means of orices or ducts 89and Sill. As particularly shown in Figure 2, the orifice 89 is incommunication with the mixing passage slightly in advance of thethrottle valve 52 for engine idling operation while the fuel orifice Si)is in communication with the mixing passage slightly to the rear of thevalve 52 when the latter is in closed position, and serves to supplyfuel to the mixing passage when the throttle is partially opened andbefore the main fuel jet is caused to operate. The upper extremity ofthe chamber 81 is closed by means of a Welsh plug 92 and the upper end0f the bore 8f3 is closed by means of a threaded plug 93 on fitting 85.

Means are provided for admitting air for admixing with the fuel suppliedto the supplemental orices 89 and 90 prior to the ejection of fueltherefrom into the mixing passage I I. A wall of the air inlet passageI4 is provided with av duet 95, the amount of air admitted through thepassage .9.5 being .controlled by a valve 9.6 which is threaded as at 91into a bore in a boss 98 formed on the carburetor body, A lknurledmanipulating portion 99 is formed on the valve 96 in order t0 facili#.tate manual control thereof. A spring lim surrounds the threadedportion of the valve member 96 adjacent the manipulating portion S9 and.Serves to provide a frictional component to retain the-valve 96 inadjusted position, A passage 1li1 establishes communication btween thezone ad jacent the valve S16 and the bore 84. In this man-` ner acontrolled amount of air may be admitted through the passages 95 and 101to the bore 84 which `zone fuel flowing through the openings B6 isadmiXed with air in the bore 8.4 a mixture of fuel and air thereafterpassing through the passage 88 and .chamber 81 for discharge into themixing passage 11 through the orices or ducts B9 and 911.

The present invention is inclusive of novel means .for metering .orregulating the new of liquid fuel from the fuel reservoir 11 into thefuel Well g4. As shown in Figures 2, 3 and Il a wall of the dependingportion 23 is bored and threaded to receive a fitting or bushing 102.The bushing 102 .is provided interiorly with a ledge vHill whichpositions a plate or cupelile member 195 in position in the fitting 182.The member Lio is pressed into or .otherwise secured in the bore 103 inthe fitting. The member 105 is made comparatively thin, a structuralfeature Which I have found forms an important part in controlling theflow of fuel into the fuel well 251, The cup 135 is Nformed with ametering or passage orifice H36 which establishes communication betweenthe reservoir 1'1 and the well 24. By making the plate or oup Itrelatively thin in dimension, the .rate of fuel flow through the passage06 will be substantiallv unaffected by variations in the viscosity gfthe fuel over a reasonable range suitable for use internal combustionengines, For example, it is a conventional prsetioe ,in the operation oftwo cycle engines to introduce a quantity of lubricating oil orlubricant into the liquid fuel in the supply tank for admixture with.the fuel prior to its passage into the carburetor. As lubricating oilused for this purpose usually has a higher viscosity factor than thefuel, the. viscosity of fuel and oil mixture is `higher than the fuelalone. 1rrespective of Whether the fuel passes through the carburetorwith or without lubricating .oil being admixed therewith, the liow ratethrough the metering orifice |06 remains substantially oonstantln orderto obtain this result of uniform flow rate through the orifice itt, theblote 'S5 may be made of a thickness up to approximately thirtytfivethousandths o f an inch Without materially affecting the rate of fuelflow through the plate. It has been found that plates -Of a thickerdimension do not function satisfactorily with varying viscosity factorsof fuel and lubricant mixture. Through the utilization of a thin plateand .orifice construction of the character illustrated in Figure 4,there is provided a simple yet effective means for establishing asubstantially uniform ow rate from the receptnole 11 into the Wellirrespective of the viscosity Q the liquid passine therethrough withinthe .range of usable .fuel mixtures for engines with which thecarburetor may be utilized.. `I. .have found bv actual and exhaustivetests that this .desirable result is obs tainable with the abovedescribed construction.

Venting means is provided for the chamber 11 in order to prevent .airlock or unequal pressure such. as would interfere with `flov/ into andout the chamber.. As illustrated in Figure 3g a opening 108 is providedto the atmosphere so as to establish .an serialized pressure in the fuelChamber l1.

The operation of this form of the invention is as follows:

F961, is introduced into the inlet passage 31 .from a fuel supply (notshown), the fuel flowing past the polygonally shaped valve member 33through the bore 31 into the fuel chamber 11. the fuel lol/el rises inthe chamber 11 the float 45 is buoyed upwardly and being pivoted Qlmover .ment around` the axis of the pin 43, the portion 49 of bracket 46urges the valve member 39 upf Wardly.. When the float has been elevateda preV determined distance in order to establish a defq inite fuel levelin thechamber l1, the pressure of erin i9; moves the valve 39 to closedposition to interrupt vfuel now into the chamber l1. When the internalcombustion engine with which the Carburetor may be used is started, theair or choke valve 6.2 is preferably closed or nearly closed in order toestablish a proportionately high vacuum to insure fuel flow into theengine. for starting purposes. After the engine is started, the airvalve 62 is moved to full open position as indicated in full lines inFigure .2. During idling operations of the engine, the throttle valve 52is in closed position as shown in Figure 2 or near closed po sition.During idling operations of the engine under the influence ofsubatmospherie pressure developed by the engine, fuel is taken upwardlythrough the tube 82 from the Well 24 where it is mixed with air in thebore 34, the air for mixing With lthe fuel beine taken in through thepassages S5 and lill. The fuel and air mixture is then oon,.- veyedthrough the duct 88 and bore 81 for dis-l charge into the mixing passageIl through the orices 39 and Sil. When the valve is in full closedposition as indicated in Figure .2, fuel is taken into the passagethrough the orifice 89 in advance of the Valve disc 52 to provide anidling mixture for the engine. When .the valve 5.2 .is partially openedand before fuel is delivered into the venturi I2 from the main fuelorifice 18, the orifice l91! delivers additional fuel and air mixtureinto the mixing passage. The valve disc or throt-Y 121e valve 52 isprovided with openings 55 in order to permit the passage of some airthrough the carburetor for admixing with the fuel and air mixturedischarged through the orifice 85 when the throttle valve 52 is in fullclosed position. the throttle 52 is moved to an open position to ih.-crease the speed of the engine, air passes through the venturi at a muchhigher rate of speed as the engine speed increases by reason of thedecrease in pressure in the mixing passage. This increase air speedthrough the venturi 12 exerts a, lift.- ,ng force on fuel in the well 2dwhereby fuel is extruded from the main fuel orifice 18 into the chokeband 1'1 of the venturi. When the main fuel jet '113 comes inteoperation, the fuel dis-.- charge from orifices 89 and Si) ceases andthe fuel mixture passing into the engine is obtained en.P tirely fromthe air passing through the venturi of the carburetor which is mixedwith fuel from the main jet 18. During high speed operation of theengine, air is bled into the fuel in Iwell 24 through the air bleedchannel or duct 80 so that an emulsion or admixture of fuel and air isdis-.,- charged into the venturi through the orice 1g. rl'he meteringorifice 136 establishes a uniform new rate of fuel from the chamber 11into the accede? well 24 so as to establish a predetermined maximum forfuel fiow from the well 24 through the main discharge orifice into themixing passage.

A modified form of fuel metering means for establishing a predeterminedmaximum flow of fuel from the chamber Il to the fuel well is illustratedin Figure 5. In this form of construction the depending portion 23 ofthe carburetor body l is interiorly threaded as at to receive thethreaded portion of a fitting I I i. The fitting I I I is formed with aninterior bore il? in which is disposed a needle valve H4, the extremityof the valve ||4 cooperating with a restricted opening in the fitting|i| for regulating the flow of fuel to the passage or duct H5. The bore||2 is in communication with the fuel reservoir or chamber I'I throughthe medium of a transverseh7 extending passage IIB formed in the fittingThe needle valve ||4 is formed with an enlarged portion III which isthreaded into a. threaded portion I i8 in the fitting I I I, the portionIl being provided with a manipulating handle or pin ||3 as shown inFigure 5. Thus the position of the valve I I4 may be regulated byrotation of the valve through manual operation of the pin H9, theposition of the valve i ifi in the orifice I I5 determining the meteringor rate of fuel fiow into the Well 24.

A stufng gland |20 is provided surrounding the portion II'I of the valveconstruction and cooperates with a threaded cup |Ei so as to preventleakage of fuel to the exterior of the receptacle i8 along the valvemember li?. The fitting II! serves a dual purpose, it encloses andsupports the needle valve II4 and also secures the receptacle I8 inposition. As shown a gasket |23 is disposed between a ledge portion |24of the fitting li! so that when the tting I I i is threaded into thedepending portion 23 of the carburetor body, the gasket |23 is broughtinto sealing engagement with the receptacle I3 to hold the latter intosealing contact with the gasket 2| in the channel 2d of the carburetorbody I3. By this means the metering of fuel may be accomplished bymanipulating the needle valve H4, the fitting supporting the valve alsofunctioning as a means for securing the receptacle I3 to the carburetorbody. The operation and functioning of the carburetor illustrated inFigure 5 is the same as that hereinefore described in connection withthe form of the invention illustrated in Figures l through 3 inclusive.

Figure 6 illustrates a further form of the invention in which thecarburetor body IIJ" is provided with a depending central portion 23".The depending portion 23" is provided with a central bore |30 in whichis disposed the fitting l5, the latter being provided with an interior-bore |3| the upper exit of which forms the main fuel extruding jet ororifice into the venturi I2". The lower portion of the walls of bore |33are threaded to receive a threaded portion |32 integrally formed on thefitting l5". The portion |32 of the fitting is formed with a restrictedopening |33 into which extends the tapered extremity |34 of a needlevalve |35. The diameter of opening |33 is such as to cooperate with thetapered portion |34 of the metering valve or needle so as to regulatethe flow of fuel from the float chamber Il into the well or bore I3I.The space |33 immediately beneath the portion |32 is in communicationwith the fuel supply chamber I'I by means of a passage or duct I3?. Themetering needle or valve |35 is made of hollow or tubular configurationhaving openings |39 in the side Walls thereof so as to permit thepassage of fuel from the fuel well |3| to the interior of the tubularneedle valve |35. r:Che upper end of the valve extends into a fitting|46 which is disposed in a bore 84", a passage |4| being incommunication with the interior of the tube |35 and the bore 34". Thebore 84 provides a mixing zone in which air is mixed with fuel passingupwardly through the valve tube |35 to supply a fuel and air mixture tothe orifices 89" and 96" for idling or slow speed engine operation. Thefitting |43 is fixedly connected to the tube |35 and is adapted to bemanipulated by a handle |43 in order to regulate the position of theneedle with respect to the metering orifice or bore |33 in portion |32.By this means rotation of the needle |35 and fitting |653 adjusts theposition of the tapered portion |34 thereof in the orifice |33 to meteror control the flow of fuel from the chamber |'I through passage |31,space |33, orifice |33 and into the well |3|. When the engine is idling,fuel from the Well i3! iiows through the openings |33 to the interior oftube |35, thence upwardly through passage |4| into the zone or space 84where the fuel is mixed with air from the passages 95 and Nil" forsubsequent discharge into the mixing passage i!" through the orifices89" and 90". An air channel or duct 3B is provided for bleeding air intothe bore |33 and through transverse openings |65 formed in the walls ofthe fitting l5 into the well |3I. In this manner a small amount of airis mixed with the fuel prior to its ejection from the main fuel orificeinto the venturi I2. In this form of construction receptacle I3 is heldin piace with respect to the body portion I5 of the carburetor by meansof a bolt Id? threaded into the interior of the depending portion 23". Agasket |48 is disposed between the head of the bolt I4? and thereceptacle I8 in order to make a fluid tight seal and prevent leakage offuel from chamber Il.

In all forms of the invention, the tube for conveying fuel from the fuelwell to the idling discharge ports extends through the main fuel jet andis disposed eccentrically therein, the tube being nearer to the airinlet so that fuel is discharged into the mixing passage from the mainjet at the right side of the tube as viewed in Figures 2, 5 and 6.

It should be further noted that in all forms of the invention the float45 is pivotally connected and supported from the body portion of thecarburetor. By this means the receptacle I8 can be quickly and easilyremoved from the carburetor body for purposes of cleaning or inspectionwithout dismantling or disassembling any of the other elements of theconstruction. In the form shown in Figure l removing the bolt 2 releasesthe receptacle from engagement with the body lil without disrupting anyof the other elements of the carburetor. In the form shown in Figure 5the fitting may be removed by rotating the same in a direction todisengage the threads with the threaded interior of the dependingportion 23 thus permitting removal of the receptacle I8. In the formshown in Figure 6 removing the bolt |47 permits the receptacle I3 to bedisengaged from the body portion I0 of the carburetor. Through thearrangement of the present invention I have been able to provide aninexpensive receptacle assembly for a carburetor providing a fuel supplychamber or float bowl which may be easily manufactured and which iscapable :inf 1quick assembly Without the use of special oo s.

9 It is to be understood that the valve 96 for regulating the amount ofair for the idling mixture may, if desired, be disposed in a horizontalposition i. e. in alignment with the axis of the channel or passage |01.This arrangement of control may be desirable when the carburetor is usedwith marine engines, and especially those of the so called outboard typeembodying panel mounting for the carburetor and engine controls.

It is apparent that, Within the scope of the invention, modificationsand different arrangements may be made other than is herein disclosed,and the present disclosure is illustrative merely, the inventioncomprehending all variations thereof.

What I claim is:

1. In a charge forming device, in combination, a substantiallyhorizontal body member, a receptacle secured to said body member forminga fuel chamber, a mixture outlet formed in said body member, a venturiformed in said body member axially aligned with the-mixture outlet, anair inlet in line with said venturi and mixture outlet and formed insaid body member, said body member having a portion depending into thereceptacle formed with a fuel Well beneath said venturi, said fuel wellhaving an opening into said venturi, a secondary fuel-air mixturedischarge orice in a wall of said mixture outlet above said venturi, asecondary air inlet in a wall of said air inlet above said venturi andarranged to admit air for admixing with fuel prior to its discharge fromsaid secondary orifice, a mixing chamber formed in said body member andlocated above said venturi, two passageways one of which connects saidmixing chamber with said secondary air inlet and the other of whichconnects said mixing chamber with said secondary mixture orifice, saidpassageways being substantially parallel to said air inlet and mixtureoutlet, a fuel line connecting said well with said mixing chamber, meansfor metering fuel flow from said fuel chamber to said fuel Well, andmeans formed in said body for admitting air into the well for admixingwith the fuel prior to the discharge thereof into the venturi.

2. In a charge forming device, in combination, a substantiallyhorizontal body member, a receptacle formed of sheet metal secured tosaid body member forming a fuel chamber, a mixture outlet formed in saidbody member, a venturi formed in said body member axially aligned withthe mixture outlet, an air inlet in line with said venturi, and mixtureoutlet and formed in said body member, the axis of the venturi andmixture outlet being nearer the fuel level in said fuel chamber than theaxis of the air inlet, said body member having a portion depending intothe receptacle formed With a fuel well beneath said venturi, said fuelwell having an opening into said venturi, a iitting in said openingprojecting slightly into said venturi and having a main orice fordischarging fuel from said Well into said venturi, a secondary fuel-airmixture discharge orifice in a wall of said mixture outlet above saidventuri, a secondary air inlet in a wall of said air inlet above saidventuri and arranged to admit air for admixing with fuel prior to itsdischarge from said secondary orice, a mixing chamber formed in saidbody member and located above said venturi, two parallel passageways oneof which connects said mixing chamber with said 10 secondary air inletand the other of which connects said mixing chamber with said secondarymixture orifice, said passageways being substantially parallel to saidair inlet and mixture outlet, a fuel line connecting said well with saidmixing chamber and passing through said tting, said main orice, and saidventuri, means for metering fuel flow from said fuel chamber to saidfuel well, and means formed in said body for admitting air into the Wellfor admixing with the fuel prior to the discharge thereof into theventuri.

3. In a charge forming device according to claim 2 and having removablemeans passing through an opening in the receptacle and engageable withthe body member for securing the receptacle to the body member.

4. In a charge forming device according to claim 1 and having a fittingconnected to said depending portion of said body member and having apassage therein for admitting fuel from the fuel chamber for dischargeinto the venturi, an adjustable valve in said passage having la por-Ytien accessible exterorly of the receptacle for manipulating saidvalve, said fitting being formed to secure said receptacle to said bodymember.

5. In a charge forming device according to claim 1 and having said fuelmetering means including a relatively thin member having a port thereinfor predetermining the fuel flow from the fuel chamber into the fuelwell.

6. In a charge forming device according to claim 1 and having said fuelmetering means including -a fitting removably disposed in said fuelwell, said fitting having a passage formed therein, a relatively thinmetaI plate extending across said passage, and a fuel metering portformed in said plate for establishing communication between said fuelchamber and said Well.

7, In a charge forming device according to claim 1 :and having said fuelmetering means including a bushing removably disposed in said fuel well,a plate carried by said bushing, the thickness of said plate notexceeding thirty-five thousandths of 4an inch, and a fuel passage formedin said plate for establishing communication between said fuel chamberand said Well.

8. In a charge forming device according to claim l and having a fittingconnected to said depending portion of said body member and having apassage therein for admitting fuel from the fuel chamber for dischargeinto the venturi, an adjustable valve in said passage operated fromabove said venturi and being accessible exteriorly of said body memberfor manipulating said valve.

BERNARDy C. PHIlll PS.

References Cted in the le of this patent UNITED STATES PATENTS NumberName Date 1,121,630 Holley Dec. 22, 1914 1,299,454 Gardner Apr. 8, 19191,453,490 Bessom May 1, 1923 1,505,565 Johnson Aug. 19, 1924 1,523,095Zarracina Jan. 13, 1925 1,632,279 Eckles June 14, 1927 1,733,730 HalingOct. 29, 1929 1,741,401 Bryan Dec. 3l, 1929 1,742,376 Beard Jan. 7, 19301,758,954 Linn May 20, 1930 1,323,017 Wolf-ard Sept. 15, 1931 2,038,206Chandler Apr. 21, 1936 2,093,011 Grosz Sept. 14, 1937

